The present invention relates to the field of the packaging of flowable products such as liquids or pasty products, particularly that of containers intended to contain beverages and more especially mineral water.
In the field of the packaging of potable water, it is commonplace to use semirigid packaging made of synthetic substances, commonly known as plastics, such as PET (poly-ethylene-terephthalate), PP (polypropylene), HDPE (high density polyethylene), etc. These packagings are generally made in the form of bottles the capacities of which are, at least in France, in most cases, between 25 cl and 1.5 liters or even 2 liters. Larger volumes are relatively infrequent, particularly on account of their weight.
Admittedly, bi-oriented PET containers of cylindrical shape or of rectangular cross diameter, the standard volume of which may be as much as 5 liters or more, are known. However, the mechanical strength of such containers is customarily low for weights of synthetic material which are proportionately higher and therefore not very economical. By way of indication, for modest mechanical properties, a 5-liter bottle requires at least 75 g of PET for the cylindrical version or at least 100 g for a standard bottle of rectangular cross diameter.
To improve the overall mechanical properties of such containers, particularly as far as their mechanical resistance to vertical crushing is concerned, the containers currently marketed have wall thicknesses which are significantly greater and reinforcing structures (bulges, stiffening ridges, etc.) which further increase the total weight of the said containers, their complexity and therefore their cost of manufacture.
There are already some solutions to provide to the consumer containers with less thick walls and therefore containing less material. The patents DE 19500006 and JP 10007121 concerns packagings allowing for the first to guarantee a complete emptying and to decrease the volume of waste and for the other to guarantee a standing position and a good compactness. In this case, it is polyethylene, which is worked by extrusion and blow-molding. In this case, the parison of the container does not allow to reach a big volume of the final container.